1.) a word used when you don't know what a thing is.
2.) a random object.
3.) a funny word to call somebody who is being weird.

1.) Mom-"Jeffy, hand me the key."
Jeffy-"Where is the damn key???"
Mom-"Over there, you know, by the dumaflache!"
Jeffy-"What the hell is a dumaflache?!?!?!?"
2.)"I found a dumaflache in the woods. Looks old. Don't quite know what the hell it does..."
3.) (your friend walks into you house, sits down in a chair, leans back, and falls out, tumbling across the room)
"Dude, your such a dumaflache!"